Light in the Deep Sea.NGSS

Home , Darkness, Deep sea, Green, Orange (colour), Visible spectrum, Wavelength

MONTEREY BAY AQUARIUM Light in the Deep Sea Topics Light, Adaptations

Grades 6-12

Site Indoors

Duration 30-45 minutes Focus Question Materials How are deep sea animals adapted to their habitat? For each group:  Deep Sea Photos  Deep Sea Data Sheets Overview #1, #2, #3 Why are so many deep sea organisms red? Students explore one camouflage strategy of  Colored felt (black, red, deep sea animals through an in-depth examination of light properties in ocean waters. orange, yellow, green, blue, purple)  Deep Sea Glasses (Deep Objectives Sea Glasses template, blue plastic film, file Students will be able to: folders, tape, scissors,  Define visible light as being made of many different colors and wavelengths. binder clips or staples)  Describe how the wavelength of light determines its ability to penetrate seawater.  Colored pencils  Investigate how deep sea organisms use properties of light to help them survive. Vocabulary camouflage, midwater, Background visible light, wavelength The Deep Sea Habitat Next Generation The deep sea is the largest and least understood habitat on Earth. It begins approximately Science Standards 200 meters (or 660 feet) below the surface of the ocean and reaches down, on average, Practices 3,800 meters (12,500 feet) to the ocean floor. The deepest part of the ocean, in the Analyze and interpret Marianas Trench, is 11,033 meters (36,201 feet) deep. Darkness is one of the defining data characteristics of the deep sea because sunlight is absorbed and scattered by the ocean water. In clear water, some sunlight can penetrate into the midwater, or “twilight,” zone Core Ideas between approximately 200 to 1,000 meters (660 to 3,300 feet). Light intensity is low but LS4.C Adaptation does allow for some animals to see. Sunlight cannot reach below 1,000 meters (3,300 feet) PS4.B Electromagnetic making this area eternally dark. Despite the darkness, deep sea organisms in these zones radiation possess many camouflage strategies that help them both find food and avoid becoming Crosscutting Concepts someone else’s meal. One camouflage technique utilized by deep sea organisms is red Structure and function coloration. The red wavelength of the light spectrum is unable to penetrate into deep ocean waters, effectively camouflaging those red organisms in the darkness of the deep sea. Performance Expectations The Light Spectrum In order to understand camouflage in the deep sea, one must have a basic understanding of See page 4 the visible light spectrum and how it penetrates ocean waters. Visible light represents a narrow band of electromagnetic radiation that appears white when all colors are present.

MONTEREY BAY AQUARIUM

The colors of the spectrum (red, orange, yellow, green, blue, indigo and violet) can be remembered using the mnemonic device: ROY G BIV, which uses the first letter of each color. Light travels in waves at a very rapid speed. Each color of the spectrum has specific VOCABULARY wavelength ranges.

Camouflage: The colors in the middle of the visible spectrum (yellow, green and blue) penetrate seawater a behavior, shape, color to the greatest depth, while colors of longer (violet) and shorter (red and orange) and/or pattern that wavelengths are absorbed and scattered more rapidly. This property of light influences the helps an organism blend in with its surroundings coloration patterns and distribution of marine organisms.

Midwater Zone: During this activity, students use blue filters in order to simulate the behavior of light at an ocean zone varying ocean depths. A colored filter allows only one color of light to pass through the 200 - 1,000 meters (660 filter; all other colors are absorbed and therefore blocked from the eyes of the viewer. In - 3,300 feet) in depth the case of the blue plastic filter, all colors except blue are absorbed and the only color that can pass through is blue light. This simulates blue light being the only light that penetrates Visible Light: the section of into deeper water. On land, an item will appear a specific color because it is absorbing all electromagnetic other colors and reflecting back its color to our eye. radiation that can be seen by the human eye Deep Sea Camouflage

Wavelength: The wavelengths of light that can penetrate into the depths of the ocean are yellow, green the distance between and blue. Because other wavelengths are not present in the deep sea, they cannot be seen. successive crests of a A color must be present in the surrounding environment in order to be seen by the eye. wave Several organisms living in ocean depths have red coloration. Their red color effectively makes them invisible in the inky darkness, because no red wavelengths are present.

Red coloration is not the only camouflage strategy used by deep sea organisms. Many deep sea organisms are able to produce their own light, called bioluminescence. Some animals, like the viperfish, possess bioluminescent organs on their bellies. As they migrate upwards to find food in shallower depths, where some visible light does penetrate, the bioluminescent organs on their bellies brighten. This matches the downwelling light making the fish disappear into the background. Some deep sea animals are transparent which allows them to blend into their surroundings. Many of these transparent animals also utilize the color red for camouflage, especially around digestive organs. These red guts hide bioluminescent prey, effectively camouflaging the predator from becoming prey itself!

Teacher Preparation TEACHER 1. Make color copies of Deep Sea Photos for each student group. You may choose to TIP source additional animal photographs found in the Animal Guide on the Monterey Bay

Save paper (and Aquarium website: www.montereybayaquarium.org. time copying) by having students record their 2. Make deep sea glasses, enough for every group of students to have at least one pair observations in a with four layers of blue film. (You may have students construct their own glasses.) notebook rather than Directions for glasses construction: printing out the  Print out the Deep Sea Glasses Template found on page 8. Use this template to cut attached data sheets. out glasses from recycled file folders.  Source blue film and cut into strips, approximately 5.5 inches long by 1.5 inches wide. Either blue plastic report folders or gels used for stage lights from theater supply companies will work.

MONTEREY BAY AQUARIUM

 Tape one blue film strip onto each pair of glasses covering the eye holes. Attach one side of the three additional layers of film together with tape. DO NOT tape down all sides of the additional film layers, as students will need to utilize them separately during the activity. CONSERVATION 3. Prepare sets of felt pieces for student groups. Each set should contain one black felt TIPS background (12-inch square) and at least one felt piece (cut into one-inch squares) of each of the following colors: red, orange, yellow, green, blue and purple. Note: The color As far away as the indigo is left out of the experiment due to its close proximity to blue and violet, as well as deep sea seems, our actions on land have the difficulty in obtaining indigo felt pieces. a direct impact on the health of this Procedure ecosystem. Some ways you can help care for the deep 1. INTRODUCE THE FOCUS QUESTION TO THE CLASS. sea are: Share the question: How are deep sea animals adapted to their habitat? You may write  Reduce the it up on the whiteboard or have students add it to their science notebook. Give students amount of trash you time to write their initial thoughts down or discuss with a partner. generate.  Be energy efficient.

 Recycle as much 2. IN SMALL GROUPS, HAVE STUDENTS EXAMINE COLORS OF DEEP SEA ORGANISMS. of your trash as Pass out copies of Deep Sea Data Sheets #1 and #2 (or project the data sheets so possible. students record observations in a notebook). Distribute a set of Deep Sea Photos to students or allow students to search for images of deep sea organisms on the internet.

3. PASS OUT DEEP SEA GLASSES AND SETS OF FELT PIECES TO EACH STUDENT GROUP. If you haven’t already constructed one pair of glasses per student group, have students do so. Then make sure each group has one large black background and one square each of red, orange, yellow, green, blue and purple felt.

4. STUDENTS EXPERIMENT WITH COLORS IN THE DEEP SEA USING THEIR GLASSES. Have student groups use the two data sheets to record changes in their ability to see the colors of felt through the Deep Sea Glasses as they add layers of blue film (representing increasing ocean depth). Students should observe that the red, orange and yellow felt pieces become harder to see. (Students may also notice that the black background ELL TIPS becomes difficult to see.) Next students observe the Deep Sea Photos using their glasses and record their ability to see the organisms as they add layers of blue film. Visual scaffolding is 5. INTRODUCE THE LIGHT SPECTRUM AND EXPLORE THE PROPERTIES OF LIGHT IN WATER. helpful for English Explain that light travels in wavelengths, and we see objects because light wavelengths language learners. reflect off of them and enter our eyes. Visible light contains a range of colors, including Demonstrate that all red, orange, yellow, green, blue, indigo and violet (ROY G BIV). Each of those colors has colors are present in white light by shining a a different size wavelength. Have students complete Deep Sea Data Sheet #3. You light through a prism in may go into greater detail by discussing light penetration in shallow versus deep ocean a darkened room. A waters. There is a Spectrum of Light in the Ocean chart on page 9 that you may share rainbow should appear. with students.

6. LEAD A CLASS DISCUSSION OF THEIR FINDINGS ABOUT CAMOUFLAGE IN THE DEEP SEA. Why is red a good color to be if you live in the deep sea? How does the color of deep sea organisms compare to the colors of shallower ocean organisms? What other camouflage adaptations might deep sea organisms have?

MONTEREY BAY AQUARIUM

9. RETURN TO THE FOCUS QUESTION. Now that students have explored the light spectrum in the ocean, have them revisit the question: How are deep sea animals adapted to their habitat? Students may think on their own or discuss with a partner. Then in their THE MISSION OF THE science notebook, you may have them draw a line of learning and under it add MONTEREY BAY to their original thoughts about the question. AQUARIUM IS TO INSPIRE Extensions CONSERVATION OF THE  Try using different colored filters, such as red and green. What colors are easy to see? OCEANS. Which colors do not pass through the filter?  Have students view images of transparent deep sea animals and discuss the advantages of this camouflage strategy.

Resources Websites Monterey Bay Aquarium www.montereybayaquarium.org Learn more about red, bioluminescent and/or transparent deep sea organisms in the Animal Guide on Monterey Bay Aquarium’s website.

Monterey Bay Aquarium Research Institute www.mbari.org View pictures and videos of deep sea organisms and read current research projects and findings from a cutting-edge research and engineering organization.

Books The Deep Sea. Robison, Bruce and Judith Connor. Monterey Bay Aquarium Foundation, 1999. The Silent Deep. Koslow, Tony. The University of Chicago Press, 2007. The Deep. Nouvian, Claire. The University of Chicago Press, 2007.

References Learning Ocean Science Through Ocean Exploration. Edited by Chase, Valerie. National Oceanic and Atmospheric Administration (NOAA), 2006. The Marine Biology Coloring Book. Niesen, Thomas M. Coloring Concepts, Inc., 2000.

Standards Next Generation Science Standards www.nextgenscience.org

Performance Expectation Relates to MS-PS4-2: Develop and use a model to describe that waves are reflected, absorbed or transmitted through various materials

Acknowledgements Adapted from “All that Glitters” in NOAA’s Learning Ocean Science Through Ocean Exploration.

MONTEREY BAY AQUARIUM

Deep Sea Data Sheet Name: #1

Look at the photographs of deep sea organisms and answer the questions below.

 What do you notice about each organism’s coloration?

 How might their coloration help these organisms survive?

 What do you wonder about them?

Now use the Deep Sea Glasses to observe how colors appear in the ocean. Record what happens to your ability to see the colored felt pieces with varying layers of blue film in the chart below. Each layer of blue film represents a deeper depth in the ocean. # of blue film layers Red Orange Yellow Green Blue Violet

Summarize your results in the space below.

How might your results relate to the coloration of deep sea organisms?

MONTEREY BAY AQUARIUM Deep Sea Data Sheet #2 Name:

Use the Deep Sea Glasses to look at the photographs of deep sea organisms. Record what happens to your ability to see the deep sea organisms with varying layers of blue film in the chart below. Use blank columns for any additional photographs of deep sea organisms you have found.

# of blue film Midwater Johnson’s sea Bloodybelly Red sea fan layers shrimp cucumber comb jelly

Summarize your results below.

Why do you think you had these results?

What implications do your results have for deep sea organisms? How might red coloration help them survive?

MONTEREY BAY AQUARIUM Deep Sea Data Sheet #3 Name:

Look at the table and diagram below. The table shows light radiation and its wavelengths. The diagram depicts a cross-section of the ocean.

Use your colored pencils to color the sections in the diagram so that they correspond to the wavelength ranges listed in the table. Notice that some colors of light penetrate deeper than others.

Type of radiation Wavelength in nanometers violet 380-424 blue 424-491 green 491-575 yellow 575-585

orange 585-647 red 647-750

Which color penetrates deepest into ocean waters?

What is happening to the other wavelengths of light as they penetrate the water?

Does this diagram support your observations on the other data sheets? Why or why not?

Describe the relationship between depth and an organism’s coloration.

BONUS: On land, where the entire light spectrum is visible, what makes a red apple appear red?

MONTEREY BAY AQUARIUM

Deep Sea Glasses Template

MONTEREY BAY AQUARIUM

Spectrum of Light in the Ocean

Image courtesy of Kyle Carothers, NOAA-OE

MONTEREY BAY AQUARIUM

Midwater shrimp Sergestes similis

MONTEREY BAY AQUARIUM

Parastichopus johnsoni Johnson’s sea cucumber

MONTEREY BAY AQUARIUM

Red sea fan Swiftia kofoidi